U.S. patent application number 12/085162 was filed with the patent office on 2010-07-08 for forming apparatus.
Invention is credited to Samuel Gwynn Buckingham, Gabriel Joan Giurgiu, Andrew Leo Haynes, Christopher John Nicholls.
Application Number | 20100173036 12/085162 |
Document ID | / |
Family ID | 38048873 |
Filed Date | 2010-07-08 |
United States Patent
Application |
20100173036 |
Kind Code |
A1 |
Haynes; Andrew Leo ; et
al. |
July 8, 2010 |
Forming Apparatus
Abstract
The present invention relates to a forming apparatus for forming
a formable material or materials. The apparatus has a first forming
tool set, and a second forming tool set. Each forming tool of the
second forming tool set is adapted to co-act with one or more
forming tools of the first forming tool set, or vice versa, to form
a co-acting forming tool in a pressure forming zone. There is a
first forming tool set guide or guides about which the first
forming tool set can be moved about a first circuit. There is also
a second forming tool set guide or guides about which the second
forming tool set can be moved about a second circuit. There is also
a drive means to drive the tools in a machine direction. At least
on part of the circuit, immediately before or after the pressure
forming zone, adjacent forming tools of one the forming tool sets
are movably supported such that the only relative movement of said
adjacent forming tools is towards or away from the forming tools of
the other forming tool set with which they co-act.
Inventors: |
Haynes; Andrew Leo;
(Auckland, NZ) ; Nicholls; Christopher John;
(Auckland, NL) ; Giurgiu; Gabriel Joan; (Auckland,
NZ) ; Buckingham; Samuel Gwynn; (Auckland,
NZ) |
Correspondence
Address: |
JACOBSON HOLMAN PLLC
400 SEVENTH STREET N.W., SUITE 600
WASHINGTON
DC
20004
US
|
Family ID: |
38048873 |
Appl. No.: |
12/085162 |
Filed: |
November 16, 2006 |
PCT Filed: |
November 16, 2006 |
PCT NO: |
PCT/NZ2006/000300 |
371 Date: |
July 21, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60736842 |
Nov 16, 2005 |
|
|
|
Current U.S.
Class: |
425/183 |
Current CPC
Class: |
B29C 48/0011 20190201;
B29C 48/12 20190201; B29C 2043/3283 20130101; B30B 11/14 20130101;
B29C 2043/5833 20130101; B29C 43/00 20130101; B29C 43/48 20130101;
B29C 2043/483 20130101; B29C 43/06 20130101; B29C 48/0017
20190201 |
Class at
Publication: |
425/183 |
International
Class: |
B29C 45/12 20060101
B29C045/12 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 16, 2005 |
NZ |
543629 |
Oct 18, 2006 |
NZ |
550637 |
Claims
1-88. (canceled)
89. A forming apparatus for forming a formable material or
materials ("material(s)"), said apparatus comprising or including,
a first set of dies or forming tools ("first forming tool set"), a
second set of dies or forming tool ("second forming tool set"),
each die or tool ("forming tool") of said second forming tool set
being adapted to co-act with one or more die or tool ("forming
tool") of said first forming tool set, or vice versa, to form a
co-acting forming tool in a pressure forming zone, a first forming
tool set guide or guides ("first guide(s)") about which said first
forming tool set can be moved about a first circuit, a second
forming tool set guide or guides ("second guide(s)") about which
said second forming tool set can be moved about a second circuit,
at least one primary drive ("first drive") to move, in serial
progression said forming tools of said forming tool sets about said
guide(s), in a machine direction, wherein, at least on part of said
circuit, immediately before or after (hereafter "lead zone") said
pressure forming zone, adjacent forming tools of one said forming
tool set are movably supported such that the only relative movement
of said adjacent forming tools is towards or away (hereafter said
"motion") from the forming tools of the other said forming tool set
with which they co-act.
90. The forming apparatus as claimed in claim 89 wherein there is a
constant referenced relationship of co-acting and/or adjacent
forming tools, one or more of each or same set, over said pressure
forming zone during which they are advanced in said machine
direction.
91. The forming apparatus as claimed in claim 89 wherein said
forming tools at said lead zone present or recede (without any
forming tool to forming tool gaps likely to entrap said material)
stepwise in an otherwise aligned condition relative to each
other.
92. The forming apparatus as claimed in claim 89 wherein in said
lead zone all of the discrete said forming tools are moving with
the same component of velocity as its neighbours not withstanding
there may be movement in the orthogonal component to provide the
requisite alignment and said motion.
93. The forming apparatus as claimed in claim 89 wherein said
motion occurs prior to ("lead-in zone") said pressure forming zone,
relative to said machine direction.
94. The forming apparatus as claimed in claim 89 wherein said
motion occurs after ("lead-out zone") said pressure forming zone,
relative to said machine direction.
95. The forming apparatus as claimed in claim 89 wherein there is a
temperature control system provided for at least one of said
forming tools sets.
96. The forming apparatus as claimed in claim 89 wherein said
forming tools are each supported on two axes ("axes of support")
transverse to said machine direction, so that in said lead zone one
of said axes of support follows a different locus in said guide to
the other thereby to allow adjacent forming tools in said lead zone
to be held in, or not to be held in, the same orientation relative
to said machine direction.
97. The forming apparatus as claimed in claim 96 wherein said axes
of support run in tracks in said guides via a rolling axis or a
guided pivot axis.
98. The forming apparatus as claimed in claim 89 wherein there are
at least two guides for each said forming tool set.
99. The forming apparatus as claimed in claim 98 wherein one each
of said at least two guides is located either side of said forming
tools of a said forming tool set.
100. The forming apparatus as claimed in claim 89 wherein at least
one of said forming tool sets and its guides can be moved relative
to the other forming tool set and its guides (e.g. under the action
of a pneumatic or hydraulic system between frames supporting said
guides) so as to effect "opening" or "closing" of said forming
tools and forming surfaces of said pressure forming zone to at
least vary the pressure in said pressure forming zone.
101. The forming apparatus as claimed in claim 89 wherein said
guides can be locking in position relative to one another.
102. The forming apparatus as claimed in claim 89 wherein said
circuits of tools are incomplete such that said forming tools can
be removed and replaced as they exit said lead-out zone and
replaced, whether with the same or another forming tool prior to
entering said lead-in zone respectively.
103. The forming apparatus as claimed in claim 89 wherein a said
forming tool can be urged over said lead zone by an adjacent
forming tool (with respect to said machine direction) and is not
linked to said adjacent forming tool other than by their
associations with their guide(s).
104. The forming apparatus as claimed in claim 97 wherein each of
said guides has two tracks at least in said lead zone, one of said
axes of support of each said forming tool follows one of said two
tracks whilst the other of said axes of support follows the other
of said two tracks.
105. The forming apparatus as claimed in claim 89 wherein said
first primary drive moves in serial progression said forming tools
of said first forming tool set about said first guide(s).
106. The forming apparatus as claimed in claim 89 wherein there is
a second said primary drive to move in serial progression said
forming tools of said second forming tool set about said second
guide(s).
107. The forming apparatus as claimed in claim 89 wherein said
forming tools are advanced by a serial engagement of each newly
presented forming tool by said at least one primary drive which
then urges the accumulated said forming tools through said pressure
forming zone and about said guides.
108. The forming apparatus as claimed in claim 107 wherein there is
at least one secondary drive to aid said primary drive, for example
in over coming friction between said guides and said forming
tools.
109. The forming apparatus as claimed in claim 108 wherein said at
least one secondary drive feeds forming tools to said primary drive
via said guides.
110. The forming apparatus as claimed in claim 89 wherein the total
length of said forming tools in said circuit is equal too or less
than the total circuit length to accommodate thermal expansion of
said forming tools.
111. The forming apparatus as claimed in claim 89 wherein said
forming tool is a composite tool of at least one carrier tool that
runs in or on said guides and at least one surface tool to provide
at least one of said opposing surfaces, said surface tool mounted
to or from said carrier tool to be carried thereby.
112. The forming apparatus as claimed in claim 111 wherein the
mounting of said surface tool to or from said carrier tool is one
that allows the surface tool to thermally expand relative to the
carrier tool or vice versa.
113. The forming apparatus as claimed in claim 89 wherein all of
said forming tools have identical thermal expansion behaviours.
114. The forming apparatus as claimed in claim 89 wherein said
apparatus is arranged such that said first and second forming tool
sets ("tool(s)") co-act in a plane so that one set of forming tools
presents down onto or toward the other set of forming tools over
said pressure forming zone.
115. The forming apparatus as claimed in claim 89 wherein there is
a further said guide present as at least one pressure plate on one
side of said pressure forming zone to bear on said forming tools in
said pressure forming zone to increase the pressure applied by said
forming tool(s) to said material(s).
116. The forming apparatus as claimed in claim 115 wherein there
are two said pressure plates, a first pressure plate above said
pressure forming zone acting on one of said forming tool sets, and
a second pressure plate below said pressure forming zone acting on
the other of said forming tool sets.
117. The forming apparatus as claimed in claim 89 wherein adjacent
and/or co-acting forming tools of said sets are locked to each
other by locking means at least over said pressure forming
zone.
118. The forming apparatus as claimed in claim 89 wherein (for
example as for injection moulding or the like) said first and
second forming tool set ("tool(s)") are such as to present the
forming tools of the respective sets to each other over a pressure
forming zone where the sets are side by side when considered with
respect to the horizontal or vertical.
Description
FIELD OF INVENTION
[0001] This invention relates to forming apparatus for
materials.
BACKGROUND OF THE INVENTION
[0002] A difficulty with forming of different kinds (whether under
pressure alone such as drawing (deep or shallow) and imprinting, or
pressure and temperature such as injection moulding, blow moulding,
extrusion, vacuum forming, thermoforming, pressure forming,
compression moulding (e.g. for rubber or cross-linkable materials)
vacuum forming in conjunction with material extrusion,
thermoforming in conjunction with extrusion and/or vacuum forming,
calendaring and post processing and similar forming processes) is
the need to ensure an ability for the apparatus
[0003] (i) to meet tolerances required,
[0004] (ii) to be brought to its operating conditions without
fouling,
[0005] (iii) to be operated whether at operating temperature(s) or
not without destructive interferences, and
[0006] (iv) to be brought to the forming zone (preferably a
pressure zone) with or without any tracked or guided movement
opening and then closing gaps that capture unwanted material.
[0007] It is to at least some of those features (i) to (iv) that
the present invention is in some aspects directed.
[0008] A difficulty, for example, in mating or co-acting dies or
other forming tools ("forming tools") is the prospect of undesired
gaps and variations in orientation over the forming zone (hereafter
"pressure forming zone"). This is irrespective of whether or not
the forming tools simply receive material under pressure (e.g.
injection moulding) or apply pressure to a material not being
introduced under pressure (e.g. extrusion and then thermoforming),
or some hybrid thereof, as there is the prospect of material being
entrapped between adjacent forming tools and thereby giving rise to
inferior production and excessive stresses and pressure(s) in the
system. Any progression of forming tools about a curve will affect
orientations and interferences. For example a prior art method (or
alternative) of moving consecutive or continuous die blocks into
position is shown in FIG. 3a (for example a pipe forming
caterpillar). The blocks are attached on a continuous linkage, for
example conveyor belt chain or otherwise, and are driven about the
circuit. As they come in to meet with each other a nip point A is
formed between consecutive blocks prior to them coming into
parallel alignment. The presence of such a nip point creates, as
can be appreciated, problems and join lines in the finished
product.
[0009] In this specification where reference has been made to
patent specifications, other external documents, or other sources
of information, this is generally for the purpose of providing a
context for discussing the features of the invention. Unless
specifically stated otherwise, reference to such external documents
is not to be construed as an admission that such documents, or such
sources of information, in any jurisdiction, are prior art, or form
part of the common general knowledge in the art.
[0010] It is to features of thermal control and/or fouling
prevention that in some aspects the present invention is directed.
It is an additional or alternative object of the present invention
to provide forming apparatus able to be operated on a continuous or
substantially continuous basis by providing requisite pressures
over a pressure forming zone between co-acting forming tools or at
least to provide the public with a useful choice.
BRIEF DESCRIPTION OF THE INVENTION
[0011] In a first aspect the present invention may be said to
broadly consist in a method of forming a material, said method
comprising or including the steps of
[0012] (i) presenting a formable material to a space (whether
substrated by, interposed by and/or associated with other material
or materials, or not), (hereafter "material") from whence said
material can be carried by and/or between opposing surfaces, as
said opposing surfaces advance in an advancing direction,
[0013] (ii) pressurising, as said opposing surfaces advance, said
material between said opposing surfaces in a reduced space between
said opposing surfaces defining at least in part a pressure forming
zone, said reduced space between said opposing surfaces being
maintained at least substantially constant until such time as the
form of at least one of said opposing surfaces is profiled into
said material and is retainable thereon, and
[0014] (iii) releasing the now profiled material from between the
said opposing surfaces, as the space increases between said
opposing surfaces as the surfaces advance,
[0015] wherein each of said opposing surfaces, or at least one said
such surface, may be provided by one or more forming tool(s) of a
series of forming tools being advanced about its own guiding
circuit,
[0016] and wherein as said forming tools present in a zone to
pressurise or release said material there is preferably no gap
between adjacent said forming tools at least where they contact
said forming material, and the relative movement between adjacent
tools of at least one of said set of forming tools over said zone
is only towards the forming tools of said other opposing
surface
[0017] Preferably said guiding circuit is endless.
[0018] Alternatively said guiding circuit is interrupted.
[0019] Preferably each of said opposing surfaces is provided by one
or more forming tool(s) of a series of forming tools.
[0020] Preferably each of said forming tools is advanced at least
in part by driving of said forming tool by a driving means through
said pressure forming zone.
[0021] Preferably said driving action is via a motor whether
hydraulic, electronic or otherwise.
[0022] Preferably each of said series of forming tools is advanced
by at least in part shunting by a trailing forming tool through
said pressure forming zone where the step (ii) pressurising takes
place.
[0023] Preferably in said pressure forming zone, where the step
(ii) pressurising takes place, each of said forming tools is
supported on one or more guide tracks acting on two axes of each
said forming tool on its flanks transverse to said advancing
direction, thereby to present reproducibly said forming tool,
insofar as orientation is concerned, in said pressure forming
zone.
[0024] Preferably in said guiding circuit, the, or both series of
forming tools, is, or are, advanced serially about said guiding
circuit by each said forming tool being pushed over at least part
of said guiding circuit under a drive action directly on just one
or a few of said forming tools.
[0025] Preferably in said guiding circuit, the or both series of
forming tools, is permitted, by a differential of locus of said
guide tracks at each flank of each forming tool at one or more zone
to vary from the mutual condition of adjacent forming tools
required through the pressure forming zone.
[0026] Preferably in said pressure forming zone where the step (ii)
pressurising takes place, one series of forming tools present
surfaces downwardly whilst an underlying series of forming tools
present surfaces upwardly.
[0027] Preferably the forming tools of the underlying series of
forming tools, when in said pressure forming zone where the step
(ii) pressurising takes place, are each supported from
underneath.
[0028] Preferably said forming tools can form a three dimensional
profile into said material.
[0029] Preferably said at least one series of tools is profiled to
imprint the profile of a liquid crystal display ("LCD").
[0030] Preferably said at least one series of tools is profiled to
imprint the profile of a photovoltaic cell.
[0031] Preferably said at least one series of tools is profiled to
imprint the profile of a text profile in said material.
[0032] Preferably said material is introduced together with a
further material, whether formable or not.
[0033] Preferably said material is a plastic material.
[0034] Preferably said material is introduced in a liquid or
semi-liquid form.
[0035] Alternatively said material can be introduced in a semi
rigid or rigid form to undergo heating immediately prior to or
within said pressure forming zone to allow forming of the
material.
[0036] Additionally said material may be individual parts that may
be introduced to be covered by another material.
[0037] Alternatively said material is pressure formed only in the
absence of any heating in the pressure forming zone.
[0038] Preferably said material is introduced in an extruded
form.
[0039] Alternatively said material is introduced in discontinuous
or discrete lengths whether in liquid, semi-liquid, semi-rigid or
rigid form.
[0040] Preferably each of the two series of said forming tools is
profiled to imprint the profile of a liquid crystal display
("LCD").
[0041] Preferably said profile is imprinted one side of said
material.
[0042] Preferably said profile is imprinted on both sides of said
material.
[0043] Preferably said forming tool is a composite of at least one
carrier tool that runs in or on said one or more guide tracks and
at least one surface tool to provide at least one of said opposing
surfaces, said surface tool mounted to or from said carrier tool to
be carried thereby.
[0044] Preferably each forming tool, or said carrying tool carrying
said surface tool, has at least two distinct follower sets, one set
engaged only during when said tool is in the pressure forming zone,
a further set thereafter used to guide said tool about the
remainder of said one or more guide.
[0045] Preferably there are multiple said pressure forming zones
with said material being further treated in between said multiple
pressure forming zones.
[0046] Preferably in addition material or materials are added
between or in said pressure forming zones.
[0047] In a second aspect the present invention may be said to
broadly consist in a forming apparatus for forming a formable
material or materials ("material(s)"), said apparatus comprising or
including,
[0048] a first set of dies or forming tools ("first forming tool
set"),
[0049] a second set of dies or forming tool ("second forming tool
set"), each die or tool ("forming tool") of said second forming
tool set being adapted to co-act with one or more die or tool
("forming tool") of said first forming tool set, or vice versa, to
form a co-acting forming tool in a pressure forming zone,
[0050] a first forming tool set guide or guides ("first guide(s)")
about which said first forming tool set can be moved about a first
circuit,
[0051] a second forming tool set guide or guides ("second
guide(s)") about which said second forming tool set can be moved
about a second circuit,
[0052] at least one primary drive ("first drive") to move, in
serial progression said forming tools of said forming tool sets
about said guide(s), in a machine direction,
[0053] wherein, at least on part of said circuit, immediately
before or after (hereafter "lead zone") said pressure forming zone,
adjacent forming tools of one said forming tool set are movably
supported such that the only relative movement of said adjacent
forming tools is towards or away (hereafter said "motion") from the
forming tools of the other said forming tool set with which they
co-act.
[0054] Preferably said motion occurs prior to ("lead-in zone") said
pressure forming zone, relative to said machine direction.
[0055] Preferably said motion occurs after ("lead-out zone") said
pressure forming zone, relative to said machine direction.
[0056] Preferably in said lead zone both said forming tool sets are
movably supported to undergo said motion towards each other.
[0057] Preferably there is a temperature control system provided
for at least one of said forming tools sets.
[0058] Preferably said temperature control system controls the
temperature about said forming tools.
[0059] Preferably at least said pressure forming zone is
temperature controlled by said temperature control system(s).
[0060] Preferably said temperature control system can raise and/or
elevate said temperatures above or below the ambient
temperature.
[0061] Preferably one of said forming tool sets moves about a
circuit whose circuit axis is at 90.degree. to the circuit axis of
the other circuit of forming tool sets.
[0062] Preferably said axes of support run in tracks in said guides
via a rolling axis or a guided pivot axis.
[0063] Preferably said guides and tracks also allow transverse
movement of said forming tools relative to said machine
direction.
[0064] Preferably there are at least two guides for each said
forming tool set.
[0065] Preferably one each of said at least two guides is located
either side of said forming tools of a said forming tool set.
[0066] Preferably said guides can be locked in position relative to
one another.
[0067] Preferably in said opposing surfaces can apply from 0.0
kg/cm2 to 250 kg/cm2 to said material therebetween.
[0068] Preferably said opposing surfaces can move from 0.0 m/min to
300 m/min said machine direction.
[0069] Preferably said opposing surfaces can imprint a texture into
said material from 1 micrometer up to 10 meters.
[0070] Preferably said forming tools move faster when outside of
the pressure forming zone, and optionally the lead in zones and
lead out zones. For example where the forming tools may be moved
from the lead out zone to the lead in zone by a separate drive
system running faster than the speed through the remainder of the
circuit.
[0071] Preferably there are multiple lead in zones and pressure
forming zones stepping down towards a final pressure forming zone
on the one forming tool set.
[0072] In a third aspect the present invention may be said to
broadly consist in a forming apparatus for forming a formable
material or materials ("material(s)"), said apparatus comprising or
including,
[0073] a first set of dies or forming tools ("first forming tool
set"),
[0074] a second set of dies or forming tool ("second forming tool
set"), each die or tool ("forming tool") of said second forming
tool set being adapted to co-act with one or more die or tool
("forming tool") of said first forming tool set, or vice versa, to
form a co-acting forming tool in a pressure forming zone,
[0075] a first forming tool set guide or guides ("first guide(s)")
about which said first forming tool set can be moved about a first
circuit,
[0076] a second forming tool set guide or guides ("second
guide(s)") about which said second forming tool set can be moved
about a second circuit,
[0077] at least one primary drive ("first drive") to move, in
serial progression said forming tools of said forming tool sets
about said guide(s), in a machine direction,
[0078] wherein, at least on part of said circuit, immediately
before or after (hereafter "lead zone") said pressure forming zone,
adjacent forming tools of one said forming tool set are movably
supported such that the only relative movement of said adjacent
forming tools is towards or away (hereafter said "motion") from the
forming tools of the other said forming tool set with which they
co-act.
[0079] Preferably said motion occurs prior to ("lead-in zone") said
pressure forming zone, relative to said machine direction.
[0080] Preferably said motion occurs after ("lead-out zone") said
pressure forming zone, relative to said machine direction.
[0081] Preferably in said lead zone both said forming tool sets are
movably supported to undergo said motion towards each other.
[0082] Preferably there is a temperature control system provided
for at least one of said forming tools sets.
[0083] A forming apparatus as claimed in claim 9 wherein said
temperature control system controls the temperature about said
forming tools.
[0084] Preferably at least said pressure forming zone is
temperature controlled by said temperature control system(s).
[0085] Preferably said temperature control system can raise and/or
elevate said temperatures above or below the ambient
temperature.
[0086] Preferably one of said forming tool sets moves about a
circuit whose circuit axis is at 90.degree. to the circuit axis of
the other circuit of forming tool sets.
[0087] Preferably said axes of support run in tracks in said guides
via a rolling axis or a guided pivot axis.
[0088] Preferably there are at least two guides for each said
forming tool set.
[0089] Preferably one each of said at least two guides is located
either side of said forming tools of a said forming tool set.
[0090] Preferably said apparatus is able to be driven in the
reverse of said machine direction, as either part of the forming
process or to allow servicing or maintenance.
[0091] Preferably said guides can be locked in position relative to
one another.
[0092] In a further aspect the present invention may be said to
broadly consist in an apparatus for forming a formable material or
materials that include at least one formable material,
("material(s)"), said apparatus comprising or including,
[0093] a first set of dies or die forming tool bolsters ("first
forming tool set"),
[0094] a second set of dies or die or forming tool bolsters
("second forming tool set"), each die or tool ("forming tool") of
the second forming tool set being adapted to co-act with one or
more die or tool ("forming tool") of the first forming tool set, or
vice versa, in a pressure forming zone,
[0095] a first forming tool set guide or guides ("first guide(s)")
about which the first forming tool set can be moved about a first
circuit,
[0096] a second forming tool set guide or guides ("second
guide(s)") about which the second forming tool set can be moved
about a second circuit,
[0097] a first drive to move in serial progression the tools of
said first forming tool set about the first guide(s),
[0098] a second drive to move in serial progression the tools of
said second forming tool set about the second guide(s),
[0099] wherein there is a constant referenced relationship of
co-acting forming tools, one of each set, over said pressure
forming zone during which they are advanced (hereafter "in the
machine direction"),
[0100] and wherein one (and preferably both) of said drives and its
guide(s) shunts or drives the tools of its forming tool set as they
are each supported on two axes transverse to said machine
direction, such axes each being selected from a rolling axis or a
guided pivot axis, so that in at least part of said circuit(s) one
axis follows a different locus to the other thereby to allow
proximate forming tools on said circuit(s) to be held in, or not to
be held in, the same orientation relative to the machine
direction.
[0101] Preferably at least one of said guides, and preferably each
of the guides, is of one or more tracks and a roller glide or other
follower of one of said axes of each forming tool follows that
whilst the other follows the other.
[0102] It is to be understood that such following of the forming
tools in or on the guides can be achieved by many ways which fall
within the scope of the present invention. For example but not
limited to roller engagement (whether bearinged, bushed or
otherwise), sliding engagement, linear bearings, cam followers and
other means known in the art.
[0103] In one embodiment the roller, glides and/or other follower
bear on a surface distinct from that on which they otherwise bear
as a consequence of gravity effects being overcome at least when
the dies are under operative pressure.
[0104] Optionally, but preferably for thermoforming, the guide(s)
over the pressure forming zone provide a pinching effect as the
dies progress into and/or through the pressure zone.
[0105] In another aspect the invention is apparatus for forming a
formable material or materials that include at least one formable
material, ("material(s)"), said apparatus comprising or
including
[0106] a first set of dies or die forming tool bolsters ("first
forming tool set"),
[0107] a second set of dies or die or forming tool bolsters
("second forming tool set"), each die or tool ("forming tool") of
the second forming tool set being adapted to co-act with one or
more die or tool ("forming tool"), or vice versa, of the first
forming tool set in a pressure forming zone,
[0108] a first forming tool set guide or guides ("first guide(s)")
about which the first forming tool set can be moved about a first
circuit,
[0109] a second forming tool set guide or guides ("second
guide(s)") about which the second forming tool set can be moved
about a second circuit,
[0110] a first drive to move in serial progression the tools of
said first forming tool set about said first guide(s),
[0111] a second drive to move in serial progression the tools of
the second forming tool set about the second guide(s),
[0112] Preferably there is a second said primary drive to move in
serial progression said forming tools of said second forming tool
set about said second guide(s).
[0113] Preferably there is a temperature control system to control
at least the forming tools to a temperature or temperatures in an
operating range or to maintain such temperature(s), or both.
[0114] Preferably there is a constant referenced relationship
of
[0115] (I) co-acting forming tools, one or more of each set, as
well as
[0116] (II) to and in advance or following forming tool of the same
die set over said pressure forming zone during which they are
advanced in the machine direction.
[0117] Preferably the guide(s) include curves about which a die can
be urged by a following die, the following die not being linked to
the more advanced die (with respect to the machine direction) other
than by their associations with their guide(s).
[0118] The temperature control can be heating, cooling or both
(e.g. heating followed by cooling to provide form holding or
cooling followed by heating (optionally with subsequent cooling)).
Such control may be achieved actively by heating and cooling
circuits which are controlled (e.g. by electronic sensing and
driving means) or may be inherent in the material selection such
that for example excess heat is conducted away, or retained.
[0119] Preferably there is at least one pressure plate on one side
of said pressure forming zone to bear on the forming tools in said
pressure forming zone to increase the pressure applied by said
forming tool to said material(s).
[0120] Preferably there are two said pressure plates a first
pressure above said pressure forming zone and a second pressure
plated below said pressure forming zone.
[0121] Preferably adjacent forming tools of said sets are locked to
each other by a first locking means at least over said pressure
forming zone.
[0122] Preferably co-acting forming tools of said sets are locked
to each other by a second locking means at least over said pressure
forming zone.
[0123] Preferably said first locking means is by a pin and slot
engagement.
[0124] Preferably said second locking means is by a Morse taper
engagement.
[0125] Preferably one (and preferably both) of said drives and its
guide(s) shunts or drives said forming tools of its forming tool
set as they are each supported on two axes ("axes of support")
transverse to said machine direction, such axes each being selected
from a rolling axis or a guided pivot axis, so that in at least
part of said circuit(s) one axis follows a different locus to the
other thereby to allow proximate forming tools on the circuit(s) to
be held in or not to be held in the same orientation relative to
said machine direction.
[0126] Preferably at least one of said guides, and preferably each
of said guides, is of two tracks and a roller, glide and/or other
follower of one of said two axes transverse of each forming tool
follows that whilst the other follows the other.
[0127] In one embodiment said roller, glide and/or other follower
bears on a surface distinct from that on which they otherwise bear
as a consequence of gravity effects being overcome at least when
the forming tools are under operative pressure in said pressure
zone.
[0128] Optionally, but preferably for thermoforming, the guide(s)
over the pressure forming zone provide a pinching effect as the
forming tools progress into and/or through the pressure forming
zone.
[0129] In any of the aforementioned apparatus the first and second
forming tool set ("tool(s)") operate in a plane so that one set of
forming tools presents down onto or toward the other set of forming
tools over the pressure forming zone. In other forms of the present
invention however (for example as for injection moulding or the
like) preferably or optionally the first and second forming tool
set ("tool(s)") are such as to present the forming tools of the
respective sets to each other over a pressure forming zone where
the sets are side by side when considered with respect to the
horizontal or vertical. Other options including presenting from any
direction or directions.
[0130] Preferably said forming tools at the commencement of the
pressure forming zone present (without any tool to tool gaps likely
to entrap material) stepwise in an otherwise aligned condition
relative to each other.
[0131] Preferably said stepwise alignment follows a locus of
movement.
[0132] Preferably said locus of movement is linear and angled
toward said opposing co-acting forming tool.
[0133] Alternatively said locus of movement is away and/or toward
said opposing co-acting forming tool and may follow a linear or
curved locus of movement.
[0134] Preferably where the movement upwards or downwards of any
one forming tool is greater than its actual thickness, such that it
would not normally engage its neighbouring blocks (both before and
after), then block extensions are present to increase the height of
the block and the interface surface that it has with its
neighbouring blocks such that the overall apparent height of the
block is greater than that of the upward or downward movement it
undertakes.
[0135] In some forms of the present invention the means by which
materials can be introduced may be before the pressure forming zone
onto dies of either forming tool set. For example by extrusion onto
one of the forming surfaces.
[0136] Alternatively additional materials, whether to be formed or
not are added within the pressure forming zone for example as
laminates to the first material to be formed.
[0137] Preferably said guide(s) include disparate loci for two
tracks or the equivalent to guide each axis of a said forming
tool.
[0138] Preferably said two tracks are at each end of the forming
tool such that there are two tracks at each end.
[0139] Alternatively said two tracks engage via said a roller,
glide and/or follower on a surface or surfaces external to said
forming surface (for example the sides of said forming tool, the
back of said forming tool or similar).
[0140] Preferably there are more than two guides presenting to said
forming tools. For example there may be one either side of said
forming tool and an additional guide running on the centre of said
forming tool to provide additional pressure in said pressure
forming zone.
[0141] Preferably the roller, glide or other follower (preferably
one at each side of said forming tool of one of said axes of
support of said forming tool is differently distanced from the
forming tool proper with respect to the other roller, slide and/or
other follower (preferably one at each side of said forming tool)
for the other axis of said axes of support the same forming tool
thereby to allow separate tracking.
[0142] Preferably the arrangement is such that there is little, if
no, gap to allow material ingress between adjacent forming tools in
a set of forming tool as it is moved through the pressure forming
zone.
[0143] Preferably however the circuit of a or each forming tool set
allows gaps to be opened and closed around curves as a result of
the slightly different action of the relevant guide(s) on the
roller, glide and/or other follower on each of said axes of
support.
[0144] Preferably through said pressure forming zone, each forming
tool does not vary in its orientation with respect to its mating or
co-acting forming tool nor relative to at least one of its own set
of forming tools which is immediately there adjacent.
[0145] Preferably said forming tools are of a kind that vary in
dimension responsive to temperature and preferably there is
sufficient play in the mounting of the forming tools to allow them,
when brought up or down to operating temperature, to meet the aims
of the present invention.
[0146] Preferably said forming tools have reinforced areas where
they locate against adjacent and/or co-acting forming tools.
[0147] Preferably the mounting of said surface tool to or from said
carrier tool is one that allows the surface tool to thermally
expand relative to the carrier tool or vice versa.
[0148] Preferably even when not up to operating temperature there
are no material capturing gaps before and after said pressure
forming zone and preferably, where there may be extrusion of molten
materials onto one of the forming tool sets prior to the pressure
forming zone, that zone of that die set leading to the pressure
zone.
[0149] Preferably there is provided a temperature control system to
bring the forming tool sets to an operating temperature. Preferably
there is a temperature control system (e.g. heating and/or cooling)
that can maintain the forming tool at an operating temperature
during use.
[0150] Preferably the temperature systems are one and the same and
preferably each relies on a temperature controlled working fluid
(for example air, gas or liquid). Preferably said temperature is
monitored.
[0151] Preferably any temperature control system provided is for
one or preferably both sets of forming tools and, as such, each
forming tool of the set can be brought to and/or be kept at
operating temperatures or temperature profile at least over said
pressure forming zone.
[0152] Preferably at least one of the forming tool sets and its
guide can be moved relative to the other forming tool set and its
guides (e.g. under the action of a pneumatic, electric or hydraulic
system between frames supporting said guides) so as to effect
"opening" or "closing" of the forming tools and forming surfaces of
said pressure zone. There optionally can be locking in a closed
condition. Closing, in the case of thermoforming or some forms of
forming, may merely mean to its effective co-acting distance of
said forming tool sets.
[0153] Preferably at least one and preferably both sets of forming
tools are advanced by a serial engagement of each newly presented
forming tool by the drive which then urges the accumulated dies
into said pressure forming zone.
[0154] Preferably said primary drives drive said forming tools
immediately prior to said pressure forming zone.
[0155] Preferably each said forming tool is individually
driven.
[0156] Preferably said forming tools are each individually driven
or alternatively driven by a drive or drives on the circuit.
[0157] Preferably there is at least one secondary drive to aid said
primary drive, for example in over coming friction between said
guides and said forming tools.
[0158] Preferably said at least one secondary drive feeds forming
tools to said primary drive via said guides.
[0159] Preferably said forming tool is a composite of at least one
carrier tool that runs in or on said one or more guide tracks and
at least one surface tool to provide at least one of said opposing
surfaces, said surface tool mounted to or from said carrier tool to
be carried thereby.
[0160] Preferably the mounting of said surface tool to or from said
carrier tool is one that allows the forming tool to thermally
expand relative to the carrier tool or vice versa.
For example if for surface tools are more of, say aluminium and
carrier tools s are of, say, steel the surface tool will expand
differently to the carrier tool.
[0161] Preferably also there are expansion joints to compensate for
expansion under thermal loading of the guides, tracks and any
supporting structures.
[0162] Degrees of freedom between the surface tool and its carrier
tool are provided by keying which allows such relative expansion of
the two.
[0163] In another aspect the invention consists in a forming
machine of a kind that co-acts forming tools to provide a three
dimensional or two dimensional form to a material or materials
introduced under pressure and/or to be pressed in a zone ("tool
co-acting zone") between moving and mating or co-acting forming
tools,
[0164] wherein each said forming tool advances a series of such
tools about its own guiding circuit,
[0165] and wherein in the at least one tool to at least one tool
co-acting zone, each said forming tool is controlled as to its
orientation relative to the advancement direction and its
disposition to its co-acting tool(s) by two guiding axes in its
guiding circuit,
[0166] and wherein one or both guiding circuits has in at least
part of said circuit has or have a first of said guided axes of a
tool in a different locus to the other of said guided axes of that
same tool.
[0167] Preferably each forming tool is of a kind that varies in
dimensions dependent on operating temperatures.
[0168] Preferably there are incomplete circuits of tools such that
dies can be removed and replaced and they exit the tool co-acting
zone and prior to entering the tool co-acting zone
respectively.
[0169] In another aspect the invention is a method of forming a
product or product stream which comprises or includes the steps of
serially
[0170] presenting a material or materials to pressure of co-acting
forming tools, each of said forming tools moving on a separate
circuit guide,
[0171] taking said material(s) in that pressurised condition as
said forming tools separately advance on their respective circuit
guide to at least a substantial set of said material, and
[0172] separating said forming tools as they advance on their
respective circuit guide to effect or allow removal of said product
or product stream.
[0173] Preferably the method can involve one or more of
[0174] a molten mouldable material,
[0175] a compression set material,
[0176] a compression formable material (e.g. aluminium)
[0177] a thermoformable material presented at a thermo-formable
temperature,
[0178] a thermoformable material to be heated by the forming tools
to a formable condition,
[0179] a thermoformable material or molten mouldable material to be
cooled by the forming tools or otherwise,
[0180] a thermoformable material to be thermoset by the forming
tools,
[0181] any of the foregoing together with one or more material of a
different character.
[0182] In another aspect the invention consists in a forming
apparatus having
[0183] a plurality of discrete forming elements ("forming
tools"),
[0184] as a circuit (whether complete or incomplete), a guide track
or tracks for each of said forming tools at a first end
thereof,
[0185] as a complementary circuit, a guide track or tracks for each
of said forming tools at a second end thereof, and
[0186] a drive or drives to act serially on said forming tools and
to urge the engaged forming tool or lead most engaged forming tool,
into abutment with its predecessor thereby to advance a plurality
of forming tools,
[0187] wherein said circuits define an alignment zone for the
forming tools in advance of a forming zone of the aligned said
forming tools.
[0188] Preferably said forming zone is platform like or is of
aligned contiguous forming tools.
[0189] Preferably said forming zone is under pressure.
[0190] Preferably said forming zone is thermally controlled.
[0191] Preferably there is at least one guide track for each said
circuit, to act on a circuit wise spaced different roller, glide,
follower of the like of each end or external surface of each said
forming tool.
[0192] Preferably all of said forming tools have an identical
thermal expansion behaviour and preferably said forming apparatus
can move said forming tools about said circuit over a range of
temperatures.
[0193] Preferably where said forming tools have a differing thermal
expansion there is allowance for this, either in the case of the
forming tools by a thermal expansion engagement between a carrier
tool and the surface tool mounted thereto (to form a composite
forming tool), or in the case of the circuit, the guide path being
longer than the total length of forming tools present.
[0194] Preferably forming tools are of substantially unitary
design.
[0195] In another aspect the invention is in combination, two
forming apparatus as aforesaid to co-act on material(s) to be
formed.
[0196] In another aspect the invention is, in operative
juxtaposition forming apparatus ("first forming apparatus") as
aforesaid, and
[0197] at least one other forming apparatus ("second forming
apparatus") as aforesaid arranged so that it, or each, moves so
that the forming elements synchronise to the movement of the
forming elements of the first forming apparatus over regions of
their co-acting (e.g. during all or part of said forming zone).
[0198] Preferably the first forming apparatus is one embodiment
defines a forming zone as a platform with which a said second
forming apparatus co-acts from above.
[0199] In yet a further aspect the present invention consists in a
continuous forming surface for forming of one or more infeed
materials, comprising or including,
[0200] a first forming tool formed or formable first surface (first
forming surface) driven to move in a machine direction,
[0201] a second forming tool formed or formable second surface
(second forming surface) driven to move in said machine direction
and lying substantially parallel and in close proximity to said
first surface
[0202] wherein to form a lead-in zone, followed by a said forming
zone, at least one of said first or second forming surfaces is
comprised of discrete forming tools mounted directly or indirectly
to a guide, each said forming tool as it traverses said lead in
zone moves only relative to its neighbouring block which movement
is towards the other of said forming surfaces.
[0203] In the foregoing aspects, preferably the discrete forming
tools are "shunted" or driven (at least in part) about the circuit
both in the sense [0204] (i) they push each other over at least
part of the circuit under the drive action on just one (or a few)
of them, and [0205] (ii) over part of the circuit orientation out
of the mutual aligned condition (as in the pressure forming zone)
is permitted by a differential of locus of one guides track at each
of the ends of the forming tools outer surfaces.
[0206] Preferably in respect of any of the aforementioned
embodiments preferably at least one circuit, and preferably both
circuits, or optionally all circuits, are substantially oval when
viewed.
[0207] Preferably a flat region of said oval of one or more of the
circuits provides said pressure forming zone and preferably also
such a flat part of the oval forms a pressure forming zone and
optionally a lead in and/or lead out zone.
[0208] Preferably an inclined part from the curved part of said
oval shape provides said lead zone towards said pressure forming
zone.
[0209] Preferably in said alignment zone all of said discrete
forming tools are moving with the same component of velocity as its
neighbours not withstanding there may be movement in the orthogonal
component to provide the requisite alignment.
[0210] Preferably said drive or drives is/are of one or two forming
tools alone on a lower part of the/or each said oval circuit.
[0211] Alternatively each said forming tool or is individually
driven.
[0212] Preferably there is engagement of adjacent forming tools at
their respective interfaces (for example mechanical or
magnetic).
[0213] As herein used the word drive may be via sprocket, friction,
magnetic, drive servo drive, meshed drive or similar known in the
art for urging a member or series of members.
[0214] Preferably said drive is in a direction where there can be a
gravity dropping of said forming elements to the drive, the drive
preferably being on a flat of the oval.
[0215] In yet another aspect the present invention consists in a
method of forming a material comprising or including,
[0216] providing a forming apparatus with a lead in zone, pressure
forming zone and lead out zone, pressure forming apparatus having
an upper forming surface and a lower forming surface to define
there between a forming cavity,
[0217] supplying to a forming apparatus at least one infeed
material
[0218] applying pressure to said at least one infeed material at
least in said pressure forming zone,
[0219] wherein at least said upper forming surface is comprised of
discrete forming tools following a locus of movement, to thus
impart a form into or onto said at least one infeed material.
[0220] As used herein with the term "flat" in respect of oval is
irrespective of the orientation of the circuit.
[0221] Preferably each said forming tool set forms at least in part
of said pressure forming zone a forming surface.
[0222] Preferably each of said forming surfaces co-act to form said
material(s).
[0223] In a further aspect the present invention consist in a
product as herein described with reference to anyone or more of the
accompanying drawings.
[0224] In a yet a further aspect the present invention consists in
a method of forming as herein described with reference to anyone or
more of the accompanying drawings.
[0225] In another aspect the present invention consists in a
forming apparatus as herein described with reference to any one or
more of the accompanying drawings.
[0226] In yet a further aspect still the present invention consists
in a product by a method or methods as herein described with
reference to any one or more of the accompanying drawings.
[0227] In any of the aforementioned embodiments preferably the
circuits are such as to provide for gaps between dies or forming
tools after passage through the forming zone or pressure zone and
prior to uptake by the drive.
[0228] The term, bolster, block, or die as used herein can be used
interchangeably, unless explained otherwise, and is taken to mean a
tool that moves along the circuit, guided directly or indirectly by
the guiding tracks, whether the forming surface is dependent
therefrom, eg by fastening thereto, or is an integral part thereof
and includes also bolsters, blocks or dies of a multi-part
construction.
[0229] The term `comprising` as used in this specification means
`consisting at least in part of`, that is to say when interpreting
statements in this specification which include that term, the
features, prefaced by that term in each statement, all need to be
present but other features can also be present.
[0230] This invention may also be said broadly to consist in the
parts, elements and features referred to or indicated in the
specification of the application, individually or collectively, and
any or all combinations of any two or more of said parts, elements
or features, and where specific integers are mentioned herein which
have known equivalents in the art to which this invention relates,
such known equivalents are deemed to be incorporated herein as if
individually set forth.
[0231] The term used generically hereafter to define an individual
forming tool, whether it is of singular or of a composite (two or
more piece) construction (e.g. a bolster to run in the said guide
to which is connected a forming surface tool) is the term "block".
Similarly a "block set" is generically equivalent to a "die
set".
[0232] Whilst right hand and left hand have been mentioned, this
can be interchangeable unless specifically stated otherwise. Also
whilst the apparatus and method has been shown to move from left to
right, this is convention only and equally the apparatus and method
could move from right to left and have been used to describe
orientations merely as shown on the pages of the drawings.
[0233] Whilst herein the terms horizontal and vertical have been
used or depicted in the drawings, it is to be understood, that
unless specified as necessary, the orientations of the apparatus
and machinery can be at any angle, for example, but not limited to
vertical, or at any angle to the horizontal or vertical, or may
vary over a range or angles.
BRIEF DESCRIPTION OF THE DRAWINGS
[0234] With reference to the accompanying drawings preferred
embodiments of the present invention are now described,
whereby;
[0235] FIG. 1 shows in side elevation a forming apparatus of the
present invention including an upper circuit of blocks and a lower
circuit of blocks defining there between a forming surface,
surfaces or cavity,
[0236] FIG. 2A shows a schematic of the continuous forming system
of FIG. 1 showing the movement in particular of the upper circuit
and blocks therein, together with the block alignment zone, lead in
zone, pressure forming zone and lead out zone, FIG. 2B shows a
similar schematic but with lead in and lead out zones at both ends
of the apparatus and on both circuits,
[0237] FIG. 3 shows a close-up view of the movement including at
FIG. 3a a prior art arrangement whereby dies, or bolsters, or tools
rotate round and create a nip point A, whereas in FIG. 3b the
movement of the block set is shown to rotate into place, at the
block alignment zone (block E), and thereafter the lead in zone
(blocks D, C, B) to move vertically down perpendicular to the
machine direction thus at the crucial point where the dies meet the
material to be formed there is no gap between adjacent die or
tools, to then carry on into the pressure forming zone, the group
of blocks moving also in the machine direction, FIG. 3c shows a
multiple lead-in zones with multiple pressure forming zones prior
to the main pressure forming zone,
[0238] FIG. 4 shows a close-up of co-acting upper and lower dies of
the blocks, together with the pressure forming cavity there between
and shows the discrete form of the tools,
[0239] FIG. 5 is a set of close up schematic views of the lead in
(and in reversed machine direction form the lead out) zones showing
the movement of block (whether of bolster and/or individual dies)
on an upper and lower track, including at FIG. 5a is an incline
toward the other forming surface, FIG. 5b is a general sigmoid
curve, and FIG. 5c is a generic curve indicating that any form can
be followed with the blocks together with forward and backward
runners at differing heights on the block,
[0240] FIG. 6 shows in side elevation a typical guide track which
the blocks can run in, showing a) a left hand top track frame with
guide track in inside elevation and b) side elevation and c) inside
elevation of a right hand top track frame and Sections AA and BB on
corresponding lines AA and BB, and d) an inside isometric view of
the guide track frame,
[0241] FIG. 7 shows left and right track frames with guide track of
the upper circuit showing the block alignment region, lead in
region to the pressure forming zone, and lead out region,
[0242] FIG. 8 shows inside views of the left and right track frames
of the upper circuit again showing the block take out points,
[0243] FIG. 9 shows a close-up of the left hand track frame along
line BB from FIG. 5,
[0244] FIG. 10 shows a close-up of the inside view of the right
hand track frame of an upper circuit, showing in detail the block
alignment zone and change in height of the lead in zone with
respect to the machine direction,
[0245] FIG. 11 shows a close-up of Detail A from FIG. 9, showing
the height difference in the upper guide track for the forward
runner and lower guide track for the backward runner of the
block,
[0246] FIG. 12 shows an upper circuit with the left hand track
frame removed showing the movement of a set of blocks (including
dies attached) and particularly the movement of the blocks as they
enter the alignment zone, downward movement in the lead in zone and
then movement in the pressure forming zone,
[0247] FIG. 13 (a-d) shows similar views to that of FIG. 6 (a-d)
with the exception that these are for the tracks frames and guide
track for the lower circuit,
[0248] FIG. 14 shows the lower circuit (with left hand lower track
frame removed) in one preferred embodiment whereby the blocks come
in to form the forming surface in a standard manner (for example
that depicted in the prior art of FIG. 3a), that is with no lead in
zone,
[0249] FIG. 15 shows a side elevation of a block with a hardened
wear plate on the side and chamfered bolster and die,
[0250] FIG. 16 shows at 16(a) a split end view of a block having
the back runner spaced wider than that of the front runner, and
16(b) a side view of a block with forward and back runners aligned,
and at 16(c) the front runner higher than the back runner, and (d)
the front runner lower than the back runner,
[0251] FIG. 17 shows in end elevation at 17(a) a block to run in
the guide tracks, and at 17(b) a plan elevation of the same block
and at 17(c) an end elevation,
[0252] FIG. 18 shows various views of the wear plates,
[0253] FIG. 19a shows in isometric view a bolster to which a die
block can be attached showing the key system present between the
die and the bolster which allows for thermal expansion of one
relative to the other whilst still retaining the mechanical
engagement of one to the other allowing transition of force in all
three directions, 19b shows a horizontal cross section through the
key zone of the carrier tool and surface tool showing the keying
and allowance for expansion in the parallel and perpendicular
directions, 19c shows a side view of the carrier and surface
tools,
[0254] FIG. 20 shows in close up a side elevation of the lead in
and pressure forming zones showing the application of material to
be formed (for example by extrusion or spray extrusion in this
case), and the lead out zone,
[0255] FIG. 21 shows in schematic view the end form of the present
invention at 21(a) a singular upper and lower die set of unequal
length, 21(b) a singular upper and lower die set of equal length,
21(c) multiple upper die sets and singular lower die set 21(d)
multiple forming apparatus with second and tertiary processes there
between, 21(e) multiple upper die sets with processing in between,
21(f) a reversed form whereby there is a continuous upper die set
and multiple lower die sets, 21(h) shows a further embodiment
whereby a set of forming tools is at least partially wrapped round
a circular forming surface (eg a drum), the forming tools producing
an opposing surface to interact with the surface of the drum, the
forming tool set having at least a lead in zone, and optionally a
lead out zone as earlier described, FIG. 21(i) shows a further
embodiment of the apparatus where the upper and lower forming tools
sets form substantially horizontal circuits that are substantially
flat, FIG. 21(j) shows a further embodiment whereby the upper
forming tool set is as per earlier description, and the lower
forming tool set is a substantially flat conveyance or track of
forming tools,
[0256] FIG. 22 shows a schematic of a control system to match the
drive of the slave die set that of the master die set including at
22(a) and 22(b) showing the comparison made of the master and slave
blocks and showing the die asynchrony and match point,
[0257] FIG. 23 shows a side view similar to that of FIG. 1, showing
the pressure plates in location and the dies, tools, or bolsters
that tools are mounted to or from bearing against the pressure
plate either side of the dies that lie in the forming zone,
[0258] FIG. 24A shows the pressure plate including at FIG. 24(a) in
plan view, 24(b) in side elevation and 24(c) in end elevation, and
FIG. 24(d) shows a close up side view of co-acting forming tools
being sandwiched between top and bottom pressure plates, and how
the followers of the forming tools sit clear of the guide
tracks,
[0259] FIG. 25 shows a number of successive dies or blocks of a set
(in this case an upper set) at the lead in zone, and the
interlocking thereof, and
[0260] FIG. 26 shows a similar view to FIG. 24 where etc co-acting
dies are locked together, 24(b) co-acting dies are locked together
with a Morse taper, and 24(c) successive dies are locked together
with a Morse taper.
DETAILED DESCRIPTION OF THE INVENTION
[0261] As used herein the term "and/or" means "and" or "or", or
both.
[0262] As used herein the term "(s)" following a noun includes, as
might be appropriate, the singular or plural forms of that
noun.
[0263] We recognise an advantage in providing forming apparatus (1)
of a kind that moves two sets of tooling parts (forming tools (11)
in procession continuously or continually when in use (regardless
of continuous or stop start motion, hereinafter referred to as a
"continuous" process) to bring a forming tool (11) into a co-acting
condition with a complementary forming tool (11) to then pressurise
or hold the co-acting forming tools against pressure to the
tolerances required for the material or materials to be formed, and
then to separate the forming tools. Such a process may be at a
controlled temperature also.
[0264] The forming apparatus (1) generally consists of a first
forming tool set (or upper die set) (3) carrying, defining and/or
forming an upper forming surface (23), and a second forming tool
set (or lower die set) (4). The lower die set (4) may run in a
second forming tool set guide or guides (6) and lies in close
adjustable proximity to the first die set (3). The lower die set
(4) may carry, define and/or form a lower forming surface (24).
[0265] Formed there between is a continuous forming region defined
by the opposing surfaces of the upper forming surface (23) and the
lower forming surface (24). The forming surfaces (23 and 24) move
in a machine direction MD as indicated. In the preferred embodiment
the upper die set has a first transverse axis (13). The lower die
set has a second transverse axis (14). Whilst the upper and lower
are used these are understood to be relative terms only and the
machine direction may be horizontal as indicated or vertical and
the transverse axes whilst shown as being horizontal (and parallel)
may be at any angle about the machine direction (whether the
machine direction is vertical, horizontal or at any other angle).
Optionally the first transverse axis (13) may be at 90 degrees to
the second transverse axis (14). For example the first transverse
axis may be horizontal and the second transverse axis (14) may be
vertically oriented.
[0266] The basic operating principle of the present invention is
the presence of the two cooperative circuits of forming tool sets,
the first forming tool set (3) and the second forming tool set (4).
The forming tools (11) are guided at least in part by and
preferably run either directly in a first and second forming tool
set guides (5 and 6 respectively). In one preferred embodiment the
forming tool (11) is largely unitary. In another preferred
embodiment the fo wing tool (11) is a composite of a carrier tool
(25) and a surface tool (28). In further preferred embodiments the
forming tools have cavities to allow venting of gasses or
temperature in the pressure forming zone for example.
[0267] The two components of the forming tool may be attached in
any convenient way that allows for thermal expansion where
necessary. This is discussed further on.
[0268] The carrier tool (25) runs in its respective guide track (5
and 6) and the surface tool (28) co-acts with the opposing forming
tools at least in the pressure forming zone to form the material
therebetween.
[0269] There may be only one guide or more than two guides
depending on the application requirements. At least one of the
forming tool sets) is shown as the upper or first forming tool set
(3) runs in a lead in zone (26) prior to a pressure forming zone
(27). The location of each of these zones is shown in FIG. 2 and in
close-up in FIG. 3.
[0270] In preferred embodiment there are multiple lead in zones and
pressure forming zones stepping down towards a final pressure
forming zone on the one forming tool set. This is shown in FIG. 3c
where there is a first lead in zone 26A, a first pressure forming
zone 27A and then a subsequent lead-in zone 26B and then a
subsequent pressure forming zone 27B. There may well be more also
as required. The same may occur for the lead out zone. Also there
may be only one such set of multiple lead in pressure forming zones
on an apparatus or multiple such ones.
[0271] The present invention utilizes a lead in zone (26) whereby
after forming tools (11)) have become parallel to each other (e.g.
forming tools D and C) they then move at an inclined path towards
the other opposing surface (also formed of forming tools of the
other forming tool set). As they also translate in the machine
direction MD the only relative movement between adjacent blocks D
and C in the lead in zone (26) is a parallel motion toward the
opposing forming surface. In this way there is no aperture
available (in the same way as a nip point A, of the prior art--FIG.
3A).
[0272] In doing so any mould line that may be imparted into a
finished product is minimal and there is no cavity or aperture (nip
point) for residual product to bunch or form in. As a consequence a
continuous forming surface is presented in the pressure forming
zone (27). An example of the resultant pressure forming zone (27)
is shown in FIG. 4 clearly there can be seen the individual forming
tools (11A) of the first forming tool set (3) that may run in the
first forming tool set guides (5). Similarly lower forming tools
(11B) run in second forming tool set guides (6).
[0273] The lower forming tools (11B) inturn form the lower forming
surface (24). As shown in this particular embodiment in FIG. 4 the
lower forming tools are out of register by 180.degree. (or by half
a forming tool), though the synchrony of the forming tools will
depend upon the application. Together the upper co-acting tool 12A
forms a set of co-acting tools with lower co-acting tools 12B and
12C.
[0274] In the embodiment shown in FIGS. 3 to 6 the upper or first
forming tool set (3) runs in a first forming tool set guide (5).
The first forming tool set guide (5) consists of a guide preferably
either side of the first forming tool set (3) (this guide however
may bear on any outer surface of the forming tool).
[0275] On the inner facing surfaces of each of the guides (5) there
is shown a guide track (29). The guide track (29) around that area
outside of the lead in zone (26), (and in this embodiment lead out
zone (30)) is substantially a single track for the forming tools.
There is no required relative movement of the forming tools to each
other out side of the lead in and lead out zones, other than the
egress away from the pressure forming (and lead out) zones to be
recycled at the lead in zone again. It is to be appreciated that in
one embodiment the forming tools are captive to the guide they are
not captive to each other, or the tool with which they co-act. They
are free to move along the guide track (29) except under the
influence of a drive means. (This will be explained in further
detail later). In the preferred embodiment there is as shown the
lead in zone (26), pressure forming zone (27) and in addition in
this embodiment a lead out zone (30). The lead out zone (30) is to
be understood to be the reverse of the lead in zone in that forming
tools move in an inclined path away from the opposing forming
surface and the only relative movement between adjacent forming
tools in this zone is a movement perpendicular to the machine
direction and away from the opposing forming surface(s).
[0276] Hereafter the description of the lead in zone will be
described (it will be understood that unless otherwise specified
the lead out zone is the reverse operation). A cross section of the
guide track (29) is shown at FIG. 9 and in close up in FIG. 11. As
can be seen there is a relatively upper guide track (31) where a
forward runner (33) of the forming tool (11) lies, and a relatively
lower guide track (32) for a rearward runner (34). At the beginning
of the lead in zone (26) the guide track (29) diverges into the
upper guide track (31) and lower guide track (32) for the forward
runner (33) and backward runner (34) respectively of the forming
tool (11). This has the effect of allowing the individual forming
tools to move downward or toward the opposing forming surface (ie
co-acting forming tools) whilst not creating any nip points or gaps
between adjacent forming tools (11D and 11F). Indeed the only
relative movement of one forming tool compared to its adjacent
forming in the lead in zone (or lead out zone) is a movement toward
the opposing forming surface (in the particular embodiment shown
this is a downwards movement of the upper forming tool). The net
effect of the individual forming tools flowing around the guides to
the lead in point of the lead in zone (26) shows that a nip point
is formed prior to the lead in zone (26) and thereafter the forming
tools whilst moving in a machine direction move relative to one
another only toward the forming surface and thereafter are in the
pressure forming zone (27). Thus where the material to be formed
may encounter the forming tools (ie in the lead in zone) there is
no nip point to capture material.
[0277] For maintenance purposes and/or changing of forming tool
profiles or similar there is a takeout point (35) on both upper and
lower guides this allows access to the guide track (29) so that
individual forming tools or the entire set can be removed,
maintained, or changed or added to. For the upper guide in some
lower pressure or feed rate applications the upper area of the
upper guide can allow removal and reinsertion of forming tools.
[0278] In addition the guide as shown may be of two pieces being a
first guide piece (36) and a second guide piece (37) these are
preferably joined via fasteners as shown in FIG. 6. The two piece
nature of the guide track allows for its length to be added or
subtracted to by adding joining sections in between which continue
the guide track (29) between the first guide piece (36) and second
guide piece (37).
[0279] The lower forming surface (24) can be formed simply by
forming tools on a conveyor style chain or conveyance system that
come around and form a conveying surface. Such a system will met
the aims of the present invention and be covered by it if it should
take tools from one end of the circuit to the other. Provided no
material to be formed is applied to these blocks prior to them
forming a continuous forming surface (ie after their nip point)
then no material may enter the nip points that may be formed. In
such a configuration the axis (14) of the lower die set may be at
90 degrees to the that of the upper forming set. For example the
lower die set may be similar in configuration to a "luggage
conveyor" and merely presents tools to con-act with the upper
forming tool set that move toward the lower surface to pressurise
the material to be formed.
[0280] Alternatively there may be a lead in zone as described above
such that there are two inclined paths of forming tools one for an
upper forming tool set and one for a lower forming tool set.
[0281] On any one individual forming tool the forward runner (33)
is less spaced out from the forming tool than the backward runner
(34), when viewed in the machine direction. In other embodiments it
may be possible for this arrangement to be reversed. This allows
the separate engagement by the forward runner (33) in the upper
(31) and lower runner (34) in the lower (32) guide tracks in the
lead in and lead out zones, as shown in FIG. 11.
[0282] In its simplest operation therefore the forming apparatus
(1) has the first forming tool set (3) running in synchrony with a
second forming tool set (4). The forming tool sets may be in phase
or may be out of phase as indicated in FIG. 4 where it is shown the
individual blocks being out of phase by 180.degree.. Whilst it is
shown in that particular embodiment that individual blocks are
mating it is to be understood that their main purpose is to co-act
whether forming tools are complimentary, mate with one another, or
leave a large cavity zone between each other.
[0283] A first drive (7) is located at the interface of the
pressure forming zone and lead in zone. By means of interaction
with the forming tools the drive means propels the forming tools
around the circuit. In one embodiment the drive means is an
electric motor (or similar propulsion means e.g. hydraulic,
electro-magnetic or similar) which drives the forming tools via a
pinion (38) on the drive means, which mates with a rack (39) which
is present on each of the forming tools, for example on the back of
the forming tool. Whilst it is shown the drive means here is at the
interface of the lead in zone and pressure forming zones it may
equally be at any point on the circuit. A further secondary drive
means (58) may be present to drive the forming tools to the first
drive (7). Such a secondary drive means may be required to overcome
friction of the guides and forming tools leading into the first
drive. A similar second secondary drive (59) may be present to aid
the second primary drive (8).
[0284] Additionally the forming tools as shown in the preferred
embodiment are free relative to one another save for the guidance
of the guide track (29).
[0285] In a similar way a second drive (8A) exists to drive the
second die set (4) around the second die set guide (6). Whilst a
second position (8B) is shown, the preferred embodiment places the
second drive at position (8A). This is important when there is a
lead-in zone on the lower or second forming tool set (4). In that
particular embodiment the second drive (8A) is located at the
interface of the lead-in zone and pressure forming zone of the
forming tool set it drives. The synchrony of the respective die
sets is controlled. This is achieved by comparing a sensor means on
each of the respective guide tracks. The speed of each of the drive
means then is sped up or slowed down dependant upon whether is lag
or lead in the synchrony of the respective die sets. The control of
the drives may be done through a computer or programmable logic
controller that in turn controls the drives. Such control may be
via for example an AC motor controller when for example the drives
are AC motors. Other controllers will be appropriate for other
drive technologies such as DC, hydraulic, magnetic etc.
[0286] Whilst there will be a set speed through the lead in zone,
pressure forming zone and lead out zone the forming tools (50) may
move faster in the recovery from the block dis-alignment zone to
being located back again at the block alignment zone. This may
occur where the total circuit length is greater than the total
length of forming tools present. Additionally as earlier stated
forming tools may be removed and other forming tools may be located
in place. Of the two co-acting forming tool sets a first of these
will be a reference drive from which the speed of the other die set
is slaved. The synchrony of the two forming tool sets is then
maintained as earlier described by sensors and controls. If the
asynchrony between the sets exceeds a certain set point then a
warning signal can be generated to indicate this to the operator or
the system may be stopped completely if such exceeding of synchrony
would be to damage the process or product.
[0287] The relative position of the first forming tool set (3) to
that of the second forming tool set (4) is controlled so that the
two can be spaced apart (for example by relative movement of their
respective guides), brought closer together or removed from one or
the other (e.g. for maintenance). This is achieved by hydraulic
rams or similar locating means either lowering the first forming
tool set relative to the second or raising the second forming tool
set relative to the first. In this way additional pressure may be
applied and this may be varied during the process or on a
per-process basis dependant upon what the final product requires.
The gap ("day light opening") between opposing surfaces can be
varied from 0 mm up to 10 metres on larger machines.
[0288] In operations where the material itself creates the pressure
in the pressure forming zone (eg by its own expansion or reaction)
then the closing between the opposing surfaces of the pressure
forming zone is fixed to create the required pressure.
[0289] Whilst herein the word circuit and continuous is used is to
be understood that these refer to the process only (even though it
may be stop started).
[0290] The forming tools themselves may be removed from the circuit
in a discontinuous nature by manual means or machine means so that
there may be more forming tools stored than is presently in the
forming apparatus. This may be the case where the requirement for
forming tool type is changing through the process, more or less
cooling or heating is required, or the form of the product going
through the machine is changing for example the process may change
from being for one type to another in the infeed materials may vary
also.
[0291] The forming tools (11) (whether a unitary or composite) have
on their edges wear plates (42). The wear plates are of a hardened
or wear resistant material (e.g. hardened steel) and act as a wear
interface for the forming tools against each other. They are
rounded at their lower corners to enable smooth transition through
the zones.
[0292] The forming tools (11) may have very slight block chamfers
(43) present again to aid movement through each of the zones. In
order for the forming tools (11) to run in the guide track (29) and
in particular to differentiate between the upper guide track (31)
and lower guide track (32) the guide track followers (22) are
displaced different lengths out sideways from the block dependant
on whether they are to engage the upper guide track (31), or lower
guide track (32). In one preferred embodiment the backward runner
(34) is preferably displaced further out the side of the block (45)
in that of the forward runner (33) such that the backward runner
(34) engages the more further out of the two guide tracks (29) (the
upper guide track (31)).
[0293] This is of course only one embodiment and the guide track
followers (22) may be further in or out in front or back depending
on the set up of the particular guide track (29). Several examples
of different height guide track followers on the block (11) may be
in line as shown in FIG. 16b, or may be out of line as shown in
FIGS. 16c and 16d and purely depends upon the disposition of the
guide track (29).
[0294] The forming tool (11) when comprised of a separate carrier
tool (25) and surface tool (28) can be subjected to temperature
changes. When the carrier tool and surface tool are made of
different materials (for example steel for the carrier and
aluminium for the surface) then due to the different rates of
thermal expansion there is relative movement between the two tools.
If the two tool components were rigidly bolted to each other the
result would be a bending or warping or buckling of the resultant
structure. Therefore an expansion interface (46) may be present
between the carrier tool (25) and surface tool (28). However at
such an interface there is preferably a keying in of the carrier
tool (25) and the surface tool (28) so that the forces can be
transmitted between the two.
[0295] In one preferred embodiment this consists of a keying in
parallel (47) to the machine direction and keying perpendicular
(48) to the machine direction as exemplified in FIG. 19. The keys
(48) and (49) extend from the carrier tool (25) (in one embodiment)
and engage with complimentary apertures in the surface tool (28).
The apertures in the surface tool (28) may be slightly larger in
size in a dimension parallel to the machine direction to the
parallel keying (47), and slightly larger in dimension
perpendicular to the machine direction for the perpendicular keying
(48). For example on a tool that is 150 mm wide, at 80 deg C.
ambient there is an expansion of 0.4 mm that needs to be taken
account of.
[0296] The net result is that the surface tool (that is constructed
with aluminium for example) can expand relative to the carrier tool
(25) under thermal influence yet still be keyed in sufficiently to
transmit the required mechanically forces.
[0297] There may also be present connection means between adjacent
forming tools of the same circuit. This may be for example but not
limited to magnetic, mechanical (e.g. linear bearings or dove
tailing) or similar to ensure that there is no gap present between
adjacent forming tools in any of the zones.
[0298] The forming apparatus (1) may also be driven intermittently
in that infeed material may be introduced and then the motion in
the machine direction stopped temporarily whilst some condition is
achieved and then restarted. Therefore the term continuous really
refers to the continuous availability of forming tools in the
process and not necessarily a continuous motion. As alluded to the
lead in zone (and the lead out zone) may be of any desired path
whether linear, curved, or otherwise and in some such situations
the "drop" that any one forming tool undergoes may be greater than
its apparent thickness. In this situation forming tool extensions
(52) may be present on that side of the forming tool (50) requiring
such an extension. In some situations (e.g. that typified by FIG.
5c) there may be a requirement for whole forming tool extensions
(52) on both sides of the block (50) to ensure that the block
interface (44) is maintained between consecutive blocks.
[0299] As can be appreciated when the guide track (29) is of a full
or semi full circuit and the followers (22) reside within the guide
track, there will be a tolerance such that the followers (22) may
slide or rotate or whatever within the guide track (29),
particularly under the action of gravity as they invert from one
side of the guides to the other. As a consequence (and the forgoing
is used as an example) when the forming tools (11) are for example
moving along the upper part of the upper guide track 5, towards the
drop point towards the forming tool alignment zone (49) they will
bear on the lower surface of the guide track (29) as they move
around into the forming tool alignment zone (49) they will change
the bearing point to be on either or both sides of the guide track
29, and then on the lower surfaces of the guide track (29). As they
move through the block alignment zone into the lead in zone (26)
under for example the action of gravity they will again bear upon
the lower surface of the guide track (29). However as they enter
into the pressure forming zone since they will be imparting
pressure to the infeed material which will lie between the upper
forming surface (23) and lower forming surface (24) then the upper
forming tool set will be forced upwards and the followers (22) will
bear upon the upper surface of the guide track (29). So it can be
seen that over the course of a rotation "or a cycle" from lead in
zone back to the lead in zone the forming tools (11) and in
particular the followers (22) will bear upon different aspects of
the track.
[0300] The forming apparatus (1) as indicated may be in any
particular orientation and the use of upper and lower in the
foregoing description is only a relative description purposes. In a
situation where gravity would not be able to feed forming tools
(11) into the forming tool alignment zone (49) then there may be
present a further drive (eg the secondary drives 58 and 59) as
required to urge the forming tools (11) to which ever zone they are
required.
[0301] The presence of chamfer on the leading and trailing edge of
each of the forming tools is required at least in a situation where
there is no lead out zone and the forming tools merely rotate away
(similar to the that of the forming tool alignment (49) and/or
dis-alignment zone). The presence of such a chamfer will prevent
the forming tools rubbing or interfering with those other forming
tools above (dealing with a forming tool on the lower track) or
those below (dealing with a forming tool on the upper track).
[0302] As alluded to, the forming tools may be subject to
temperature variation. As a result there will be expansion and or
contraction of forming tools relative to one another, relative to
the guide track in which they are to operate and also of the
forming tool components. The net effect therefore will be the
increasing and decreasing of the total length of the forming tools
available. If there was no variation in the guide track length
allowed for then the total length of the forming tools may exceed
the length of the guide track and thus damage would result. There
is therefore tolerance greater than the expected total thermal
expansion or contraction of the forming tools (and/or the frame) to
accommodate such expansion and/or contraction.
[0303] In certain applications there is the need to obtain high
clamping pressures between adjacent dies. Such high clamping
pressures, for example clamping pressures of 260 kg/cm.sup.2
(approximately 25 MPa) may be needed where injection moulding
processes are present in or near the pressure forming zone 27. In
some applications the forward runner (33) and the backward runner
(34) may be strengthened together with their respective guides.
However in high clamping operations this is bulky, expensive and
largely unnecessary as the high clamping pressure is only required
in the pressure forming zone 27. Such forces may exceed also that
that can be imparted (eg by hydraulic, mechanical, pneumatic etc)
on the guides and thus the followers of the forming tools.
[0304] In the preferred embodiment where high clamping pressures
between co-acting forming tools are required a pressure plate 100
is present in the pressure forming zone 27. In the preferred
embodiment there are two such pressure plates, a top pressure plate
100 and a bottom pressure plate 101. These lie at least within a
substantial portion of the pressure forming zone 27 and in the
preferred embodiment extend over its entirety.
[0305] The pressure plate consists of load bearings 102 that bear
on the lower surface of lower forming tools (11B) and the upper
surface of upper forming tools 11A. In the preferred embodiment the
load bearings (102) are arranged in an overlapping array formation
as shown in FIG. 24A. This provides a constant and substantially
even pressure against the forming tool (11) currently passing over
or under them. In other embodiments there may be one large
continuous load bearing over the substantial area of the pressure
plate (100), or there may be two long thin rows or any combination
of high load applying bearings. In other embodiments the pressure
plates may be provided by a load bearing surface, whether of slides
or liquid (eg an incompressible fluid such as water).
[0306] In the embodiment shown the load bearings (102) are recessed
into the plate (100), (102) to give the plate a low profile. The
main requirement of the pressure plate is that it is sufficiently
rigid to resist the load required to be applied to the forming
tools). In other embodiments the pressure plate may be separate for
each of the arrays if required, or may be part of the forming tool
set guides either side of the forming tools. IN other embodiments
the pressure plates may be additionally supported by internal
frames of the guides.
[0307] In use the forming tools (11) come into block alignment zone
49 and then into the lead in zone 26 as earlier described. As they
enter the pressure forming zone 27 they encounter the load
bearing(s) 102. If the pressure plate was not present the runners
of the block would run in the guides to place the pressure on the
dies. However with the pressure plate there the runners are moved
vertically clear of the guides.
[0308] The runners of the lower forming blocks 11B are lifted clear
of the guides by the upward urging of the bottom pressure plate
101. The runners of the upper forming tools 11A are lowered clear
of the guides by the downward urging of the top pressure plate 100.
As the upper forming tools and lower forming tools meet each other
in the pressure forming zone they (and the material 62 to be
formed) are essentially "sandwiched" between the top pressure plate
100 and the bottom pressure plate 101.
[0309] The force or pressure that can then be applied to the
forming tools and material 62 to be formed in the pressure forming
zone 27, is then only a function of the force that can be applied
to the pressure plates 100 and 101 and the pressure that they can
withstand.
[0310] To aid the movement of the forming tools 11 the pressure
plates 100 and 101 may be angled. For example the top pressure
plate 100 may be angled upward at or toward the lead in zone 26 to
the pressure forming zone 27. The same may occur in the transition
from the pressure forming zone 27 to the lead out zone (30). This
will aid the entrance and exit of forming tools and will also apply
the pressure gradually to the forming tools. Similarly the bottom
pressure plate may be angled downward at or toward the lead in and
lead out zones.
[0311] Further methods of creating greater pressure in the pressure
forming zone may involve magnetic elements that attract each other
across the pressure forming zone the create high pressure. The same
can be achieved for locking adjacent forming tools together. The
magnetic force may be varied in known ways to achieve the required
force between co-acting and/or adjacent blocks.
[0312] In further applications of the present forming apparatus 1
there is a requirement to keep matching adjacent and/or co-acting
forming tools, aligned very precisely to each other. This is
desirable when the form to be imparted to the material is required
to be indexed either along the pressure forming zone, or either
side thereof. Such alignment can be of adjacent forming tools in
the set to each other vertically and horizontally (perpendicular to
the machine direction MD) and also of co-acting forming tools above
and below the pressure forming zone. In some situations it is
desirable to lock both successive dies 25B and 25C together as well
as the dies they co-act with below or above as the case may be.
[0313] Such alignment in one form can be achieved by use of lasers
and grid markings, or by measurement of forming tools in the
pressure forming zone and their relation to one another and then
adjusting the relative location of the forming tools (eg by
advancing or retarding the drive or one or more forming tools or
sets of forming tools).
[0314] In the preferred embodiment such alignment is achieved by
physically locking adjacent forming tools together. This can be
achieved by a lock that only locks in one dimension, for example a
pin 105 in a slot 106 as shown in FIG. 25. The slot opens toward
the forming tool forward of it and its width-wise axis is
horizontally oriented. The slot 106 is substantially the same width
as the diameter of the pin 105. Therefore the pin and slot as shown
in FIG. 25 can only move vertically relative to each other, and
cannot shear in a manner transverse to the machine direction
MD.
[0315] To enable engagement of successive forming tools 11A and 11D
the length of the pin 105 cannot be longer than the depth of the
slot 106, unless the slot 106 is further opened away from the curve
locus of the lead in zone 26.
[0316] In a similar way as shown in FIG. 26A co-acting forming
tools above 11A and below 11B each other are locked together by a
pin 105 locating in a hole 107 of substantially the same diameter.
In this way co-acting forming tools cannot move relative to each
other in the horizontal plane (i.e. in the plane of the pressure
forming zone 27).
[0317] In such instances where locking is required the head of the
pin, or taper is shaped to allow easy mating with the hole or slot
it is to lock with. Additionally the slot 106 or hole 107 may also
be shaped to allow easier mating initially.
[0318] In the most preferred embodiment the locking system between
successive and co-acting forming tools is with a Morse taper as
shown in FIGS. 26 A and B. The taper allows easy initial mating and
then locks tight when the two forming tools are brought under
pressure--either by the clamping force of the pressure zone or the
driving force of one forming tool successive to another.
Method of Use and Process of Manufacture
[0319] The apparatus has a machine direction MD and has on at least
one forming tool circuit the key zones of a forming tool alignment
zone (49), lead in zone (26), pressure forming zone (27).
Optionally a lead out zone (30) is also present on that circuit. In
other embodiments the lead in zone may be provided on one circuit
and the lead out zone provided on another circuit (for example the
lead in zone may be on the upper forming tool circuit and the lead
out zone may be on the lower forming tool circuit). In other
embodiments still there is a lead in zone on both circuits and also
a lead out zone on none, one or both of the circuits. Typically
immediately after the lead out zone is a forming tool dis-alignment
zone 63.
[0320] The speed of such a system can be from anywhere from just
over 0 metres per minute up to 1000 metres per minute. In preferred
embodiments this range is between 2 and 100 metres per minute and
the exact set point will be dependant on the end feed material
characteristics together with the processing of that material.
[0321] The pressure forming zone 27 has, as the name suggests, at
least pressure applied between the two opposing forming surfaces
(which between them form a forming cavity) and may additionally
have temperature or a temperature profile applied which is applied
to either heat or cool the resultant product in the cavity. The
thermal control of the apparatus (and at least the pressure forming
zone) is achieved by a temperature control system. There may be
separate systems for bringing the forming tools to temperature
(whether above or below ambient), maintaining the ambient thermal
fluid about the forming tools, and for the temperature profile
control in the pressure forming zone. Alternatively they may be the
one system controlling different zones and working fluids. The
working fluids that can be used to control the temperature can be
water, air, gas, oil or similar working fluids known in the art.
The temperature control systems are those known in the art
also.
[0322] The temperature may be controlled by spraying or blowing the
working fluid onto or through the area to be controlled. For the
forming tools there may be a thermal circuit within it that can
receive a working fluid to control the forming tool temperature. In
other embodiments thermal control may be achieved electrically eg
by heater elements or Peltier effect cooling elements. From example
as the forming tools move over the circuit they can become engaged
with varying thermal fluid delivery devices to deliver thermal
fluid into a port of the forming tool and flood internal cavities
of the forming tool.
[0323] The material 62 to be formed can be supplied by extrusion on
to for example the lower forming tool surface and may be laid at
any point up to said pressure forming zone. Pressure may then be
created on the material by either its own expansion or its entering
a reduced space of the pressure forming zone to effect its forming.
In other methods discrete shots of material 62 can be laid on the
forming surfaces and thereafter formed upon entering the pressure
forming zone.
[0324] Whilst there might be a number of varying infeed materials
62 to the forming apparatus (1) at least one of these must be able
to be affected or acted upon by the pressure forming zone. Such
action may be catalysed, created, or formed by the action of
pressure and or heat but the end result is that at least that one
infeed material has a formed change imparted to it. For example a
ductile material such as a sheet metal may be feed in with various
infeed materials above and below it and the metallic material or
malleable material is thus formed into the desired shape in the
pressure forming zone and regardless whether the other infeed
materials are affected by the pressure forming zone provided that
at least that one infeed material (in this instance is sheet metal)
is achieved then the object of the invention will be achieved.
[0325] Further example materials that may be fed into the forming
apparatus (1) are as follows. Various thermal formable materials
may be used such as but no limited to polystyrene, high impact
polystyrene, polycarbonate, aquilobutalstyrene (ABS), nylon, and
all acrylics and not just those limited to crystalline polymers.
Various thinner plastic materials may be used such as amorphous
polymers but not limited to amorphous polymers and may be for
example polyethylene (PE), low density polyethylene (LDPE), low low
density polyethylene (LLDPE), thermo-plastic urethane (TPU),
thermoplastic ethylene (TPE) and polypropylene (PP). For example
there may be a polypropylene from 1 to 20 layers fed into the
machine and with the appropriate dies in place there may be plates
and bowls or similar dished or shaped materials formed. Further
thermoset materials may be used such as rubbers, phenolic and the
like.
[0326] The basic breakdown of materials that may be formed in the
forming apparatus (1) are those that will retain shape or take on a
shape or imprint under pressure alone (for example malleable or
ductile metals, plastics or alike) thermo plastic compounds that
require heat to enable them to be formed, thermo setting compounds
that require heat or some other form of catalyst in addition with
pressure can be formed, or in general thermo formable compounds
that require heat and pressure to allow formation thereof. As an
example a rubber can be pressure formed but also with the addition
of heat may facilitate further cross linking of the rubber
molecules so that one the pressure and heat are removed the shape
imparted to the rubber material is retained. In other infeed
materials it may be the pressure which forms the material and the
heat which sets the material off for example in thermo setting
materials or two pot or more materials which require heat as a
catalyst.
[0327] For example an infeed of pre impregnated carbon fibre could
be one such infeed material the application of pressure forming the
material and the application of heat setting the material off and
curing the matrix or a proxy. One of the important aspects of the
present forming apparatus (1) is that if the material to be formed
is incompressible in its solidified state then to avoid damage to
the apparatus and to maintain a viable cleaning process the infeed
material should be in a molten or semi-molten or a pliable state
prior to the heat forming zone. As it passes through the heat
forming zone the varying temperature profile that is applied will
allow or may allow the product to form and set.
[0328] The reason for incompressible material to be made molten or
pliable state is relatively obvious when one considers that with
the application of pressure to an incompressible material damage
will result unless either the apparatus or the material can move.
In some instances where there is a likelihood of an incompressible
material becoming solidified then the upper and lower forming
surfaces may be moveable relative to each other such as in the
embodiment where the frames are moveable relative to each other via
hydraulic or bellows means which is maintained at such a pressure
to allow a blow off or fail safety to be present so that relative
movement of the two is permitted if a certain pressure threshold is
exceeded. In some emergency situations or when a certain threshold
pressure is reached the lower guides and forming tool may be
dropped in relation to the upper forming tools to relieve the
pressure.
[0329] When one of the infeed materials is polycarbonate or a
similar rapid solidifying plastics material (or the like) that
shrinks upon solidification then there is a general pulling away
from the die. This can be countered if, for example, the dies form
a pinching zone at or near this stage of solidification so that
there is a reduction in mould cavity according to the approximate
shrinkage rate of the material upon the solidification. This aids
to support the material where it may be solidified yet still in a
fragile state.
[0330] For materials that are compressible whether they have
solidified or not it is an advantage to lock the two forming
guides, the upper and lower forming guides relative to each other,
where the material is incompressible upon solidification, it would
be desirable not to lock the upper and lower forming guides
relative to each other. This is because to lock the guides relative
to each other for an incompressible material will result in
buckling and possible failure and breakage whereas in a
compressible material will deform and therefore not result in
breakage.
[0331] The pressure forming zone (27) may in one embodiment have an
initial zone where temperature is maintained so that the infeed
material is in a formable and pliable state, thereafter pressure
forming of that molten or pliable material, following this a region
of cooling may occur and this will lead to a formed and set
material. The pressure forming zone may therefore be described as a
compaction or pressure form zone, a compaction or pressure form
zone transition to forming, a cooling and forming hold zone and
thereafter a release in transition to the lead out zone. It is to
be understood that the pressure forming zone is at least in part a
form holding zone and the various other parameters required to
achieve this on the'infeed material will be present for example as
discussed heat but also the addition of other chemicals or gasses,
cooling, or any other catalyst or condition present to act upon in
the infeed material.
[0332] The infeed material may under go a pre-process prior to
entering into the forming apparatus (1) or as part of the forming
apparatus whereas pre-gauged to a desired material thickness for
the process when its time to go. Whilst herein the term forming has
been used this is to be understood to be 3D in nature may also be
imprinting or merely the application of a surface finish whether
this is laminated or formed into the product or created in the
product as a result of any of the material conditions therein. It
may for example be that the use of a chemical introduced into the
infeed material at some point of the process will result in a
differing material finish.
[0333] In its simplest form the forming apparatus has been
described as having an upper track and lower track. These may be of
course the same length or may be of unequal length. Further
variations of this however are envisaged for example where there
are multiple top stations, meaning there is one single lower die
set and disposed above that are multiple upper die sets. A further
variation on this again would be the interposing of other processes
between the multiple top stations to achieve for example addition
of further material, objects or similar. Such other processes may
annealing or seal or cure or add to the materials present, change
their form or possibly even remove (for example punching or die
cutting).
[0334] Yet another variation again is multiple forming apparatus
interposed with other processed for example a full forming
apparatus consisting of an upper and lower track, a process in
between for example further annealing or heating, thereafter
followed by a further forming machine further process and further
forming machine. Whilst this has been referred to as upper multiple
tracks and singular lower tracks it could of course be the opposite
or there could be partial overlap of tracks and similar. There may
further be an association with the forming apparatus the presence
of injection units whether these move or do not move with the
forming tools (11) such injections units may serve to form
injection moulding, blow moulding or filling of cavities with
fluids (for example food stuffs, operative liquids and so). In the
situation where the injection unit is moving it will shuttle back
and forth after it is filled and performed its operation and there
may be multiple injection units to cater for the fast flow speeds.
The apparatus can also be used to form food stuffs, for example
doughs and solidifiable product. For example ice-cream can be
injected into a mould and then frozen off. The apparatus may also
be used for manufacturing an array or encapsulated articles, eg
photo voltaic cells, imprinted articles, eg CDs and DVDs (blank and
including imprinting the information on the media), screens for LCD
devices, roofing tiles, gaskets and similar. Three dimensional deep
forms such as cups can be vacuum moulded into the material,
materials introduced into the formed cavity and then the cavity and
material sealed (eg food stuffs sealed in containers).
[0335] In yet other embodiments there may be one of more forming
tools sets operating on a common lower forming tool set as shown in
FIG. 21, with operations such as pick and place etc occurring
between each forming tool set. Alternatively there may be several
discrete sets of forming tools apparatus with processes occurring
in between (such as additional moulding etc). A further embodiment
is shown where a drum 260 has a set of forming tools 3 wrapped
around to present a forming surface to that of the drum 260. The
set of tools 3 has a lead in zone 26, a pressure forming zone 27
and optionally a lead out zone 30.
[0336] In a further embodiment one of the forming tools sets is a
substantially planar conveyance system of forming tools as shown in
FIG. 21(j). The upper forming tools set (3) is a normal circuit,
whilst the lower forming tool set (4) is a planar array of forming
tools (11). This the general movement of the lower set of forming
tools (4) is a recirculation in a horizontal plane, whilst the
upper set of forming tools is a recirculation on the vertical
plane. The transverse axes 13 of the upper forming tool set (3) is
horizontal, whilst the second transverse axes (14), that of the
lower forming tool set is vertical. Whilst only one lead in zone 26
is shown on the upper forming tool set, it is to be understood that
the lower forming tool set (4) may also have a lead in, and
optionally a lead out zone. In other embodiments the lead in zone
may be on the lower forming tool set (4).
[0337] In a further embodiment the forming tools sets both form
substantially planar parallel conveyance systems as shown in FIG.
21(i). Both sets of forming tools recirculate about a substantially
parallel planes to each other (in this case horizontal). As shown
only the upper forming tool set (3) has a lead in and lead out zone
(optional), however it is to be understood that the lower forming
tool set (4) may be a lead in zone also, and optionally a lead out
zone. Alternatively the lower forming tool set (4) may have the
only lead in zone and optional lead out zone.
[0338] The foregoing description to the invention includes
preferred forms thereof. Modifications may be made thereto without
departing from the scope of the invention.
* * * * *